Salima Saxton

Clem and her friends Ash and Zara are members of the Thames and Tide Club! Every weekend they go mudlarking by the river, searching for treasures that have washed up on the shore.

Clem has found old things, new things and a whole heap of rubbish. But one day, she finds something really special. Something magical that belongs in the river and must be returned to its rightful owner… or else.

Before they know it, the Thames and Tide Club are on the weirdest, wildest, underwater-iest adventure they could possibly have imagined on a mission to save Underwater London!

Zélie is often accused of being a witch, but she doesn't believe in magic. Until Jules climbs up from the reeking Parisian sewer and hands Zélie the golden locket he discovered there. The locket once held the magical Snakestone, and Zélie knows that if she can find the stone, she might also find her missing father.

But a dangerous secret society are equally desperate to get their hands on the Snakestone and its powers. With their lives under threat, Zélie and Jules embark on a desperate hunt for the treasure, facing strange riddles, a mysterious circus, and the miles of murky tunnels that twist beneath the ancient city above...